mirror of
https://gerrit.wikimedia.org/r/mediawiki/extensions/Scribunto
synced 2024-12-04 20:58:13 +00:00
144 lines
4.3 KiB
Plaintext
144 lines
4.3 KiB
Plaintext
LuaBit
|
|
------
|
|
LuaBit is a bitwise operation lib completely written in Lua. It's
|
|
written in the belief that Lua is self-contained.
|
|
|
|
The supported operations are: not, and, or, xor, right shift, logic
|
|
right shift and left shift.
|
|
|
|
Several utilities are designed to leverage the power of bit operation:
|
|
1. hex: a dec <-> hex number converter
|
|
2. utf8: convert utf8 string to ucs2
|
|
3. noki: convert nokia pc suite backuped SMS file to .txt
|
|
|
|
Under the MIT license.
|
|
|
|
Visit http://luaforge.net/projects/bit/ to get latest version.
|
|
|
|
Status
|
|
------
|
|
Now LuaBit is in v0.4.
|
|
Release date: Mar 18, 2007
|
|
|
|
Content
|
|
-------
|
|
3 files are there for LuaBit:
|
|
1) bit.lua
|
|
is the bitwise operation lib, all operations are implemented here.
|
|
|
|
2) hex.lua
|
|
is a helper lib for ease of using hex numbers with bitwise
|
|
operation.
|
|
|
|
3) noki.lua
|
|
a utility(based on bit and hex) to convert Nokia PC Suite backuped
|
|
SMS to a unicode .txt file, which is more accessible than the
|
|
original .nfb or .nfc file.
|
|
|
|
4) utf8.lua
|
|
convert utf8 string to ucs2 string
|
|
|
|
How to use
|
|
----------
|
|
Bit
|
|
---
|
|
Just require 'bit' in your project and the bit lib will be
|
|
available:
|
|
bit.bnot(n) -- bitwise not (~n)
|
|
bit.band(m, n) -- bitwise and (m & n)
|
|
bit.bor(m, n) -- bitwise or (m | n)
|
|
bit.bxor(m, n) -- bitwise xor (m ^ n)
|
|
bit.brshift(n, bits) -- right shift (n >> bits)
|
|
bit.blshift(n, bits) -- left shift (n << bits)
|
|
bit.blogic_rshift(n, bits) -- logic right shift(zero fill >>>)
|
|
|
|
Please note that bit.brshift and bit.blshift only support number within
|
|
32 bits.
|
|
|
|
2 utility functions are provided too:
|
|
bit.tobits(n) -- convert n into a bit table(which is a 1/0 sequence)
|
|
-- high bits first
|
|
bit.tonumb(bit_tbl) -- convert a bit table into a number
|
|
|
|
Hex
|
|
---
|
|
For ease of using hex numbers, a utility hex lib is also included in
|
|
LuaBit. You can require 'hex' to use them:
|
|
hex.to_hex(n) -- convert a number to a hex string
|
|
hex.to_dec(hex) -- convert a hex string(prefix with '0x' or '0X') to number
|
|
|
|
With hex, you can write code like:
|
|
bit.band(258, hex.to_dec('0xFF'))
|
|
to get the lower 8 bits of 258, that's 2.
|
|
|
|
Noki
|
|
----
|
|
require 'noki', to save your sms to .txt file:
|
|
noki.save_sms('nokia.nfb', 'sms.txt')
|
|
and you can view the output sms.txt in notepad or other editor which
|
|
support unicode.
|
|
|
|
Utf8
|
|
----
|
|
require 'utf8', to convert a utf8 string:
|
|
ucs2_string = utf8.utf_to_uni(utf8_string)
|
|
|
|
History
|
|
-------
|
|
v0.4
|
|
* utf8 to ucs2 converter(utf8.lua).
|
|
* clean up for compatible with Lua5.1 and 5.0.
|
|
* add 'How to use' section for bit.lua and hex.lua.
|
|
|
|
v0.3
|
|
* noki added as an application of bit.
|
|
* typo correction.
|
|
|
|
v0.2
|
|
* add logic right shift(>>>) support: bit.blogic_rshift.
|
|
* add 2 utility functions: bit.tobits and bit.tonumb.
|
|
* update hex.to_hex(in hex.lua) to support negative number.
|
|
|
|
v0.1
|
|
LuaBit is written when I do my own game project(Fio at http://fio.edithis.info).
|
|
When loading resources, I have to do some bit operation. And I do not
|
|
like the embedded way of bit operation. So I decide to implement those
|
|
ops in lua. And that's LuaBit. It's not as fast as the embedded one, but
|
|
it works. And Lua is self-contained :-)
|
|
|
|
To-Do List
|
|
---------
|
|
v0.1
|
|
It'll be useful if LuaBit support those bitwise op like:
|
|
bit.band(258, '0xFF')
|
|
ease to type and use. This will be supported in next release.
|
|
|
|
v0.2
|
|
I decide to delay this feature to later version for it'll mess up the
|
|
interface of LuaBit.
|
|
|
|
v0.3
|
|
May more utility functions add to Noki - phonebook might be a nice candidate.
|
|
|
|
v0.4
|
|
There's no UCS2 -> UTF8 convertion now, this feature may add in next release
|
|
or when the project need.
|
|
|
|
Noki'll be be exluded from LuaBit in next release; I decide to let Noki grow
|
|
into a powerful tool to support more Nokia PC Suite backup format(.nfb,
|
|
.nfc and .nbu).
|
|
|
|
Trial Noki demo at http://nokisms.googlepages.com/(in Chinese)
|
|
|
|
Known issues
|
|
------------
|
|
LuaBit doesn't play very well with negative number. The return value of the
|
|
bitwise operations might change to positive when applied on negative numbers
|
|
though the bit sequence is correct. So if you want do some arithmetic with
|
|
the result of bit operation, be careful.
|
|
|
|
Feedback
|
|
--------
|
|
Please send your comments, bugs, patches or change request to
|
|
hanzhao(abrash_han@hotmail.com).
|